Synthesis, physical properties, antimicrobial potentials of some antibiotics complexed with transition metals and their effects on alkaline phosphatase activities of selected rat tissues

Abstract

Metal complexes of ampicillin trihydrate, chloramphenicol and oxytetracycline with Ni(II), Fe(III) and Co(II) chloride salts were prepared using standard methods. The geometry and the mode of binding of complexes have been proposed on the basis of chemical analysis, conductivity measurements, molec-ular weight determinations and spectroscopic studies. Ampicillin and oxytetracycline coordinated through the oxygen of the hydroxyl group and carbonyl group, and also through the nitrogen of the lactam group and amide group, respectively, in the complexes. Chloramphenicol coordinated through oxygen of the nitro group and carbonyl group and through nitrogen of the imines group in its mixed complexes. Thus, the three ligands used acted as terdentate ligands.Antimicrobial properties as well as the effect of administration of the metal complexes at the dose of 3.33 mg/kg body weight, thrice daily for 5 days on the alkaline phosphatase (ALP) activities of rat kidney, liver and serum were evaluated. Compared with their parent antibiotics, there was increase in the values of the physical properties of the metal complexes. The zone of inhibition for Escherichia coli, Staphylococcus aureus andKlebsiella pneumonia were significantly (P 0.05) in the serum enzyme. The results revealed more desirable physical properties and enhanced antimicrobial activities upon complexation with the metal ligands. The increased ALP activities in the tissues may have its consequential effect on the tissues. Key words: Metal complexes, complexation, antibiotics, antimicrobial properties, alkaline phosphatase.